JQuery+CSS实现图片上放置按钮的方法

本文实例讲述了JQuery+CSS实现图片上放置按钮的方法。分享给大家供大家参考。具体分析如下：

position:relative日常应用的时候一般是设置给position:absolute;的父层的,
父层position:relative; 子层position:absolute;的话, 就是依照父层的边界进行定位的,
不然position:absolute 会逐层向上寻找设置了position:relative的元素边界, 直到body元素..

第一种写法（连同CSS一起追加进去）

var freeOne="";
freeOne=$(".freePreviewOne").attr("data-url");
if(freeOne==null){
 //没有免费视频
}else{
 $("#coursePicture").append("<a class='hide-650 fade5' "+
  "style='top:94px;left:150px;position:absolute;z-index:100; " +
  " width: 180px;height: 60px;border: 2px solid white;" +
  "display: block;color: white;text-decoration: none;" +
  "letter-spacing: 1px;font-size: 16px;line-height: 20px;" +
  "text-align:center;padding-top:18px;" +
  "background-color: rgba(0, 0, 0, 0.44);" +
  "-webkit-backface-visibility: hidden;-webkit-transition: all .3s ease-in-out;" +
  "-moz-transition: all .3s ease-in-out;-ms-transition: all .3s ease-in-out;" +
  "-o-transition: all .3s ease-in-out;" +
  "border-radius: 10px;'"+
  "href='#modal' data-toggle='modal' "+
  "data-url='"+freeOne+"'> "+
  "<span class='contactus' style='font-size:26px;'>试 看</span> <span class='glyphicon glyphicon-play' style='font-size:20px;top:0;bottom:2px;'></span> </a>"
  );
}

页面：

<div class="es-row-wrap container-gap course-cover">
 <div class="row row-5-7 course-cover-heading">
 <div id="coursePicture" class="col-sm-5 picture hidden-xs" style="position: relative;">
 <#if course.coverImage?has_content>
  <img src="${course.coverImage}" class="img-responsive" width="436px" height="245px" />
 <#else>
  <img src="/resources/assets/img/default/course-large.png" class="img-responsive" />
 </#if>
 </div>
 </div>
</div> 

第二种写法：

//在课程图片上放置按钮
/* <a class="button hide-650 fade5" href="#modal" data-toggle="modal" data-url="/course/hyjgz2np/lesson/preview?lectureId=hyjgz2np0.49618492345325650.04212287697009742"> <span class="contactus"><strong>试看</strong></span> </a>
*/
//$("#coursePicture").append("<a class='btn btn-sm btn-info' href='#' style='top:120px;left:180px;position:absolute;z-index:100;'>试看</a>");
var freeOne="";
freeOne=$(".freePreviewOne").attr("data-url");
if(freeOne==null){
 //没有免费视频
}else{
 $("#coursePicture").append("<a class='freePreviewPicture hide-650 fade5' "+
  "href='#modal' data-toggle='modal' "+
  "data-url='"+freeOne+"'> "+
  "<span class='contactus' style='font-size:26px;'>试 看</span> <span class='glyphicon glyphicon-play' style='font-size:20px;top:0;bottom:2px;'></span> </a>"
  );
}

页面：

<style>
.freePreviewPicture{
 top:94px;
 left:150px;
 position:absolute;
 z-index:100;
 width: 180px;
 height: 60px;
 border: 2px solid white;
 display: block;
 color: white;text-decoration: none;
 letter-spacing: 1px;font-size: 16px;
 line-height: 20px;
 text-align:center;padding-top:18px;
 background-color: rgba(0, 0, 0, 0.44);
 -webkit-backface-visibility: hidden;
 -webkit-transition: all .3s ease-in-out;
 -moz-transition: all .3s ease-in-out;
 -ms-transition: all .3s ease-in-out;
 -o-transition: all .3s ease-in-out;
 border-radius: 10px;
}
</style>
<div class="es-row-wrap container-gap course-cover">
 <div class="row row-5-7 course-cover-heading">
 <div id="coursePicture" class="col-sm-5 picture hidden-xs" style="position: relative;">
 <#if course.coverImage?has_content>
  <img src="${course.coverImage}" class="img-responsive" width="436px" height="245px" />
 <#else>
  <img src="/resources/assets/img/default/course-large.png" class="img-responsive" />
 </#if>
 </div>
 </div>
</div>

运行效果图如下：

希望本文所述对大家的jQuery程序设计有所帮助。